Emptiness

I've been dreaming of empty buildings and empty rooms.

Emptiness 
To dream of emptiness suggests that there is something missing or lacking in your life. It symbolizes fruitless labor, an emotional void, or loneliness. There is nothing to show for all the effort that you have dedicated to a project or relationship. In particular, to dream that a container is empty represents optimism.

http://dreammoods.com/cgibin/dreamdictionarysearch.pl?method=exact&header=dreamsymbol&search=empty